If several micro-optic parts are to be assembled into a unit, these parts as a rule must be very precisely aligned with each other and subsequently secured in this position. Particularly if light is to be coupled into the optical fiber, tolerances on the order of magnitude of 1 .mu.m and lower must be maintained. Active adjusting methods have been proven, whereby the parts are inserted into the optical path and are adjusted in their installed position until the light beam has the desired characteristics. This is usually a very time-consuming manual labor, whereby the parts are adjusted by means of highly precise positioning units while a suitable measuring instrument is constantly observed.
An electro-optical module is known from patent disclosure No. DE-C1-43 42 844 (Honsberg et al), in which microlenses inserted into cutouts are used as a stop for a laser lock. This achieves a precisely defined distance between the laser lock and the imaging lenses placed before it, which are also inserted into the cutouts. The laser lock must be actively adjusted in the lateral direction, i.e. vertically to the propagation direction of the emitted light.
A device for arranging a block-shaped part on a silicon support is known from U.S. Pat. No. 5,453,827 (Lee). FIG. 5 shows a side view of this arrangement. The substrate SUB has a rectangular cutout AUS, into which the block-shaped part FIL--in this case an interference filter--is inserted. After the insertion, the part FIL is actively adjusted and cemented to the bonding areas KLE. The rectangular cutout is usually produced by means of a precision saw cut. The production of such a saw cut is very expensive since the actual width B of the cutout can only deviate slightly from the specified width. If the cutout is too wide the part FIL has too much play in the cutout, which makes the active adjustment more difficult. On the other hand, if the cutout is too narrow the part cannot be inserted into the cutout.
With an accurately produced saw cut and low production tolerances for the part, the side walls of the part are not flat against the side walls of the saw cut, but are separated by a thin air gap, as is made clear in the enlarged illustration of FIG. 4. In addition, since the surface on which the part rests is uneven due to the sawing, the position of the part in the sawed cutout cannot be accurately established. This is also the reason why an active adjustment cannot be omitted in this case.